Fuel injection means



`lune 28, 1932. C. D. sALlsBURY FUEL INJECTION MEANS Filed Feb. 1l, 1931III llllll INVENTOR (ar/ 5a/waxy Patented June 2s, 1932 UNITED STATESPATENT OFFICE CARL D. SALISBURY,'0F CLEVELAND, OHIO, ASSIGNOR T0 WINTON"ENGINE CORPORA- TION, OF CLEVELAND, OHIO, A CORPORATION 0F DELAWARE FUELINJECTION MEANS 'l Application led February This invention relates vtofuel injection means for engines operable on the Diesel or a similarcycle wherein combustion is had by injection of liquid fuel into acombustion chamber when the latter contains air so high- 1y compressed'that combustion will occur as injection is had.l

For each cylinder of such anengine the injection appara-tus will includean injection pump having a f plunger to be actuated through la workingstroke each time injection is to be' had tothat cylinder. Particularlywhen the engine is to operate at a high speed, as is the modern trend,the injectionperiod must be exceedingly brief, in fact almostinstantaneous; so that the period extends over 11, 1931. Serial No.514,971.

ton but may continue through variable portionsof said stroke. Furtherobjects of the invention are to ei'ect cutoH by relief of and/also tovary lthetime of such relief to vallythe cutoff. i riefly, the transmiseon, means comprises a pair of communicating cylinders, one of largerdiameter thanl the other, with pistons therefor, the larger piston beingassociated with the cam-actuated gear and the smaller pistonWith-theinjection plunger; so that cutoff 'may be effected byvariablyterminating the stroke of the injection plunger, this in turnaccomplished merely by relief of pressure between the pistons, and thisin only 'a very few degrees vof movement of the'sturn nicelyaccomplished by arranging, a

engine crank. Consequently the rise on the usual cam by which theinjection gear is actuated must be Very steep. Aswill be appreciated,there is a limit to the steepness of a ,cam rise, and the fuel injectionart has advanced to about the maximum in'this.

YAn object of this invention is to increase the-action of the injectionplunger over thatl of the follower of the actuating cam, so thatinjection may be more 'rapid than heretofore,

yet without the attendant difficulties above described. f' W Moreparticularly itis an object to accomlish this by hydraulic transmissionmeans mterposed between a timed actuating member of the mechanical gearwhich receives motion, and the injection pump plunger, by whichtransmission means the working stroke of the injection plunger may beeffected by lesser motion of said actuating gear member. By hydraulictransmission means is meant one wherein a substantially noncompressibleliquid is employed, and still another object of the invention is toemploy the fuel itself as such liquid..

To control theengine output the successive fuel charges must be varied,and as will be appreciated such variation should be by j that injectionmay always commence at the beginning of the working stroke of thepisport to be uncovered by the smaller or following piston. The mannerof varying the time of uncovering this port, which is a furtler objectof the invention, is by the simple expedient of providing on theport-controlling piston a port-controlling shoulder advancing along thepiston as it advances thereabout, so that adjusting the piston about itsaxis will vary the time ofV port opening.

Although generally speaking it is true that commencement of injectionshould take place at the beginningof the working stroke of the piston,yet where the speed range or flexibility of the engine is great, it isdesir` able that the time of commencement of injection be slightly'advanced as the throttle is opened, that is, as the injection charge isincreased. It is still a further object of this invention to provide forsuch advance auto.- matically and in lesser degree than the retard oflnjectiolcutoff. v

As" another object this control of commencement of injection is madedependent upon variation in cutoff in that both will coincidentallyfollow adjustment of a single control member. Briefly this again isaccomplished` by providing a port to be controlled by the injectionplunger, providing adjustment for closing of`this port by adjustment ofthe plunger on its axis, and finally by connecting the plunger for suchadjustment with the follower piston of the hydraulic transmission means.

pressure in my described hydraulic system,y

Finally an object of the inventionis to provide in such describedinjection apparatus al1 injection .valve which will be unseatedinwardlyof its' nozzle under predetermined injectionpressure, and which willl r'ling portion of the following hydraulic piston; and Fig. 3 is anenlarged detail of the nozzle end of. the apparatus wherein an alternateformof' injection valve control ap.v

pears. j l. ,l I l j With reference nowv to the drawing, 1 is a portionof the combustion chamber wall of one of the lengine cylinders. The wallis fa j double wall to provide the usual water jacket l kfor thecylinder, andl a through opening 2 is provided therein to receivetheinjection apparatus to be described. v

The larger part of this injection apparatus is a body 3 including at theinner face of the wall a nozzle`4. Actuallyi for convenienceof'fmanufactureand assembly the body is made up of a number of separateparts, but these parts are secured together in assembly to provide astationary body unit in'which the-movingparts are enclosed or mounted;so that for the present purpose the l by Jthe plunger 6.

term body is-used to include all of the fixed or stationary parts of theinjection apparatus which appear in' Fig. 1.

The cylinder 5, then, is a part of the body in which the injectionplunger'6 moves, these parts including the fuel injection pump providingthe expansible chamber 7 adjacent the nozzle 4 by which, fuel may beforced through .the minute nozzlel orifices 8 into the combustionchamber of the engine. The plunger 6 has a head 9 against which bearsone end of a compression spring 10, the opposite endof which bears inthebody 3; whereby theplunger is yieldably urged outwardly. A port 11 isprovided in the cylinder 5 to connect the chamber 7 with'the space aboutthe spring 10, and so located as to be controlled Thus assuming theplunger at the outer end of its stroke as shown, with its head 9 bearingupon the shoulder 12of the body, the port 11 is uncovered by thelplunger so that fuel may enter and fill the chamber 7. Upon adownwardstroke of the plunger to contract the chamber?, fuel, will leavethe chamber by way of the port 11 until the port is covered by theplunger. Thereafter, the fuel will be U5 trappedin the chamber and canfind escape of these parts therefrom only by'way of the nozzle orifices8, so that injection into the combustion chamber will be had.

The plunger 6 has a central opening 13 in which fits the stem portion 14of the injection*valve 1.5,.which seats within the nozzle 4. Theinjection valve-is yieldably maintained irnseated position by a comression spring 16, seating between a flan e l on the valve and ashoulder 18 of the ody of the apparatus. The opening 13 of the plungeris vented to the space'23 about the spring 10 by a transverse opening19.

. The sectionalarea ofthe stem 14 of the I injection valve beinggreaterjthan the injection opening controlled by the valve 15,

lwhen sulicient pressureIt is built up in the ed to prevent` drip intothe combustion chamber.

A connection 20 with a source of fuel supply provides delivery of fuelto the pump chamber 7 by Way of the leads 21, 22, the chamber 23 inwhich the spring 10 is located, the annular passage 24 and the port 11,-all K being of the body as will be understood;

The body 3 'has a pair of communicating cylinders 25, 26, aligned withthe cylinder 5 of the injection pump. The diameter vof the cylinder 25is greater than that of the cylinder 26, and pistons 27 and 28 areprovided for the cylinders. The smaller piston 28'has bearing againstthe head 9 of .the injection pump plunger through the memberA 29 whichhas rectangularly disposed ribs seating in transverse grooves in theparts to rigidly associate the parts against relative angular movementabout their common axis, yet make allowance for misalignment. Thearrangement will be recognized as that of the Oldham coupling.

The larger piston 27 is `arranged to receive motion from the cam 30acting through a rocker 31. A collar 32 rigidly secured with the piston27 outside the body 3 extends thereabout to provide a seat for acompression spring 33, the opposite end of which bears against the body3 so that the piston 27 is caused to follow the motion of the rocker 31l the described hydraulic transmission means,

' ton 28. .Y

That axial adjustment ofthe piston 27 may be had, so that the pis/ton 28 and the plunger Gmay be correspondingly?adjusted, the collar 32 isprovided onone'side with gear teeth 36, and a rack 37 is arrangedtointerirfesh therewith so that endwise rack movement Will rotate thecollar. The face of the rack is of sufficient width vthat the rackposition will control that of the collar during operation oftheapparatus. y

A port 39 is arranged between the lead 22 and the cylinder 26 to'`provide a connection for liquid supply to the chamber 381 the liquidhere employed being the fuel itself. That A the stroke of the piston 28may terminate at varying times before the end of the stroke of 'thepiston 27, I provide for varably timed openingof the port 39. To thisend I trim the upper end of the piston 28 as indicated Fig. 2 to providea` shoulder 40 pf helical characteristic extending along the piston itextends thereabout. Obviously when the shoulder 40 passes the port- 39',when the 85 piston 28 is moving downwardly to impart a working strokelto the plunger 6, the port 39 will be opened and relieve pressure inthe `chamber 38 between the pistons 27 and 28.- Thereafter, the strengthof the spring 1()4 stroke of the plunger 6 is terminated, injectionstops. And by adjustment lof the piston 28 about its axis, as bylongitudinal adjustment of the bracket 34, a different portion` of theshoulder 40 IInay be brought to registry with the port'39 so'A that thelatter will be opened at a correspondingly'different instant in thestroke of the piston 28. Thus the time of injection cutoff is dependentupon the adjustment of the piston28 about its'axis. That the time ofcommencement of injection may bevaried, the end face of thepump plunger6 is provided with a shoulderilccooperable with the port 11 as theshoulder 40 `was cooperable with its'port 39. A helical characteristicis here given to the should-er, as by facing off the plunger upon anoblique plane. Then, since bythe coupling 29 angular adjustment of theplunger will follow that of the two pistons 27 and 28, the time ofclosing of the port .11 will be Ivaried when the time of opening oftheport 39 is varied, so that the time of commencement of injection will bevaried when the time of cutoff of injection is varied. `But the pitch orslope of the shoulder 41 is' less than that of the shoulder 40 so thatfor a given change inl timeV of cutoff of injection there will be lesschange in the time of Commencement of injection.

In Figs. 1 and 3 theparts are shown in throttle-Tclosed or foff positionwherein cutoff is advanced to a maximum and commencement of injection isdelayed or retardedA to its maximum. Here it will be observed that theport 39 will be opened as the port 11 is closed so that substantially noinjection will take place and the engine will not run. As, however, thecollar 32'is turned left-hand, Fig. 1, thatportion of the shoulderl() inline with the port 39 will be raised, and that portion of the plungershoulder 41 in line with the port 11 will be lowered so thatcommencementof 'in-Y In the drawing the cam 30 is not in position toaHect the rocker 31 so that the springs 10 of the pump plunger and 33 ofthe piston 27 have both moved theirv actuated parts to their eXtremepositions in sprung direction. j

It will b,e apparent that the described hydraulic transmission meansoperative between the rocker 31 and the injection pump,

has an amplifying effect as to motion so that y pump plunger movementinitiated by the cam 30 may be greater than the rise of the cam lobeand, therefore, this rise need not be as steep as heretofore, for thesame effect; o1" a greater effect may be l as steep as heretofore. Itwill further be observed that the stroke of the pump plunger' is notonly greater than the constant motion of the mechanical actuating gearbut is also variable although the mechanical motion is constant.

In ,the detail, Fig. 3 a number of 'spring disks 16a having perforations1Gb are employed to perform the functions of the spring 16 of Fig. 1,whereby the volume of the pump chamber 7 may be decreased. Otherwise theparts and their functioning are as before.

What I claim is s I .1. In fuel injection apparatus of the classdescribed and including an injection pump .plunger and a timed actuatingmember therefor, hydraulic transmission means effective between saidparts to receive motion from said actuating member and ilnpart saidmot-ion with amplified effect to said plunger, said transmission meansincluding communieating cylinders of different diameters and pistons forsaid cylinders, and control means for terminating the working stroke of-said plunger to correspondingly effect cutoff of lnjection, andcomprising valve means arranged to relieve pressure between saidpistons.

obtained :from a rise pistons for said cylinders, one of said cylin-Vdershaving a port 'and its piston being arranged to control said port torelieve ressu're between' said pistons upon predetermi ed pistonmovement.

3. In fuel injection apparatus of the class I described and including aninjection pump plunger and a timed actuating member therefor h draulictransmission means effectivebetween said parts to receive motion fromsaid actuating member andimpart said motion Vwith amplified effect t0said plunger, saidv transmission means including communicating cylindersof different diameters and pistons for said cylinders, the smallercylinder having a port and its piston being arranged to control saidport to relieve pressure between said pistons upon vpredetermined pistonmovement.

4. In fuel injection apparatus of the class described and including aninjection pump plunger and a timed actuating member therefor, hydraulictransmission means effective between said parts to receive motion from`said actuating member vand impart said motion with amplifiedeffect tosaid plunger, said transmission means inclu/ding communieating cylindersof different diameters and pistons for said cylinders, control means forterminating the working stroke of said plunger to correspondingly effectcutoff of' injection, and comprising valve means arranged to relievepressure between said pistons, and means for controlling the time ofopening of said valve means.

5. In fuel injection .apparatus of the class described and including aninjection pump plunger and a timed actuating membertherefor, hydraulictransmission means effective between ysaid parts to receive motion fromsaid actuating member and impart said motion with amplified eil'ect tosaid plunger, said tr-ansmission means including communi-j eatingcylinders of different diameters vand pistons for said cylinders, thesmaller cylinder having a port in its side wall, and its piston having ashoulder of helical characteristic ,on a corresponding wall portion, andmeans for adjusting said piston about its axis whereby the time ofopeningsaid port may be varied. c .g

6. In fuel injection apparatus of the class described and including an`injection pump plunger and a timed actuating member -there- `forhydraulic transmission means effective between said parts to receivemotion from ysaid actuating member and im'partsaidfm'otion withamplified e'ect to said plunger, said transmission means includincommunicating cylinders and pistonsfor said cylinders, one

of said cylinders having a port in its sideJ wall and its piston havingashoulder'on 'a correspending wall portion and of helicalcharacteristic,means interassociating said pistons to allow relative longitudinalmovement therebetween but prevent relative angular movementtherebetween, and vmeans associated .to be controlled by the plunger,'said plunger having a corresponding shoulder portion of helicalcharacteristic, and means for adjusting said plunger aboutits axiswhereby the time of closing said opening may varied, to vary thecommencement of injection.

8. Inpfuel injection apparatus of the class described and including abody having an injection pump plunger movable in4 a cylinder thereof, atimed actuating member, hydraulic transmission means effective betweensaid parts to receive motion from said actuating member and impart thesame to said plunger,

said transmission means rincluding communicating cylinders and pistonfor said cylinders, one of the cylinders having a port in its side walland its piston having a shoulder on a corresponding wall portion and ofhelical characteristic, means for adjusting said. piston about its axiswhereby thetime of opening said port may be varied to vary cutoff ofinjection, said plunger cylinder having a fuel passage opening in thewall thereof to be controlled by said plunger, and the plunger piston toadjust the samel having a corresponding helical shoulder porv tionwhereby adjustment of the plunger about its axis will varyv the time ofcommencement of injection, and means associating, said plunger with saidadjustable piston to cause plunger adjustmentwith piston adjustment. v

9. In fuel injection apparatus of the class described and includinga-body having an injection pump plunger movable in va cylinder thereof,a timed` actuating, member, hydraulic,l transmission means effectivebetween said parts .to receive motion. from said actuating member andimpartthe same to said plunger, said transmission means includingcommunicating cylinders and v pistons for said cylinders, one of thecylinders having a port in its side wall'and its piston having ashoulder on a corresponding wall portion and of helical characteristic,means for adjusting said piston about its axis whereby the time ofopening said port may be varied to vary cutoff of injection, saidplunger cylinder having a fuel passage-opening in the wall thereof to becontrolled by said plun er, and the plunger havinga corresponding elicalshoulder portion whereby adjustment of the plunger about its axis willvary, the time of commencement of injection, and means associating saidplunger with said adjustable piston to cause plunger adjustment withpiston adjustment, the parts being so proportioned and arranged that ascutoff is advanced, commencement of injection will be retarded.

10. In fuel injection apparatus of the class described and including abody having an injection pump plunger movable in a cylinder thereof, atimed actuating member, hydraulic transmission means elfective betweensaid parts to receive motion from said actuating member and impart thesame to said plunger, said transmission means includingcommunicatingcylinders and pistons for said cylinders, one ofthecylinders havingaJ port in its side wall and its piston having ashoulder on a corresponding wall portion and of helical characteristic,means for adjusting said pis' ton about its axis whereby the time ofopening said port may be varied to vary cutoff of injection, saidplunger cylinder having a fuel passage opening in the wall thereof `tobe controlled by said plunger, and the plunger having a correspondinghelical shoulder portion whereby adjustment of the plunger about itsaxis will vary the time of commencement of injection, and mea-nsassociating said plunger with said adjustable piston to cause plungeradjustment with piston adjustment, the parts being so proportioned andarranged that as cutoff is advanced, commencement of injection will beretarded but in lesser degree.

In testimony whereof I hereby affix my signature.

CARL D. SALISBURY.

